Adhesive occlusion systems

ABSTRACT

System and methods of delivering adhesive material are described for occluding target locations within a patient. The systems include a catheter configured to deliver adhesive to a target location and one or more of a light source to harden the adhesive, a retention structure to contain the adhesive prior to curing, a balloon to occupy a target location, and an open cell foam plug to occupy a target location.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 62/511,214 filed May 25, 2017 entitled Methods and Devices Relatedto Treatment of Left Atrial Appendage, which is hereby incorporatedherein by reference in its entirety.

BACKGROUND OF THE INVENTION

The invention deals with the field of embolic compositions used toocclude a treatment site to provide a therapeutic benefit, deliverysystems for embolic compositions, and methods of delivering emboliccompositions.

Embolic agents, including embolic coils, embolic meshes, tissueadhesives, and liquid embolics among other agents are used to occlude atarget site within the vasculature. These agents can be used to treat avariety of conditions. A non-exhaustive list of conditions includesaneurysms, atrial septal defects, patent foramen ovale, left atrialappendage occlusion, patent ductus arteriosus, fistula, arterio-venousmalformations, fallopian tube occlusion for the purposes ofsterilization, and occlusion in the peripheral vasculature.

Of these conditions, treatment of the left atrial appendage (LAA) can beparticularly challenging since this small ear-shaped sac in the musclewall of the left atrium is highly volatile and subject to high pulsationpressure due to its close proximity to the heart. For people with atrialfibrillation or irregular heartbeat, the heart impulse is irregularwhich can cause blood to collect in the LAA and clot over time. Theseclots can later migrate out of the LAA causing stroke issues.

Tissue adhesives are compositions which physically adhere to tissue.Tissue adhesives are typically used to seal vessel punctures. Sometissue adhesives are designed to harden upon exposure to light,including UV light. These compositions can be thought of asphotopolymers which change properties when exposed to light, in aprocess known as curing. The compositions include a photo-initiatorelement which reacts with the adhesive upon exposure to light. Onceexposed to light, constituent elements of the tissue-adhesivecomposition cross-link, resulting in a hardened composition which alsoadheres to tissue. The adhesive is delivered in a liquid or gel form toa treatment site, then exposed to light, and the adhesive then reacts byhardening or curing in response to bind to tissue. The compositions aretypically hydrophobic and thus resist being washed away from blood.These light-activated adhesives are known as hydrophobic light-activatedadhesive gels. Since these adhesives stick to the tissue, these systemscan offer increased occlusive advantages since the solidified adhesivecan fill a target space as well as adhere to the tissue—mitigatingpotential risk that the composition will flow out of the targettreatment site.

Adhesive occlusive systems and/or adhesive occlusive delivery systemscontaining a light source that can be used to cross-link and harden alight-activated adhesive would be useful in order to occlude a treatmentsite. The occlusive systems could solely utilize a light-activatedadhesive, or could utilize a light-activated adhesive along withadditional occlusive or embolic compositions to occlude a treatmentsite. Such a system would augment occlusion since the occlusiveformation would also adhere to tissue, creating a complete occlusivemass which is unlikely to migrate.

Adhesive occlusive systems that do not require light-activation toharden would also be useful in occluding a treatment site. However, dueto the time necessary for these adhesives to harden, it can be difficultto maintain the liquid adhesive at the desired treatment site for theduration of the hardening/curing process.

There is a need for a device that can more effectively treat theabove-mentioned conditions and especially left atrial appendageconditions.

SUMMARY OF THE INVENTION

An adhesive occlusion system is described. The system includes acatheter having a lumen used to deliver one or more embolic agents,where one of the embolic agents is a liquid or gel adhesive whichcross-links and hardens and adheres to tissue upon exposure to light.The adhesive occlusion system includes a light source in order toactivate the adhesive, and cause it to solidify and adhere with thetissue.

In one embodiment, the adhesive occlusion system utilizes a fiber opticmember (such as an optical fiber or fiber optic cable) linking to thelight source and an ultraviolet light as the light source.

In one embodiment, the adhesive occlusion system includes a single-lumencatheter. The lumen is used to deliver the adhesive gel, and the lumenalso has an optical fiber or fiber optic cable therein. In anotherembodiment, the occlusive system includes a single-lumen catheter wherean optical fiber or fiber optic cable sits outside of the catheter.

In one embodiment, the adhesive occlusion system includes a dual-lumencatheter. One lumen is used to deliver the adhesive, as well as otheroptional embolic agents. The second lumen includes an optical fiber orfiber optic cable which links to a light source used to activate alight-activated adhesive.

In one embodiment, the adhesive occlusion system includes a sealingstructure at the distal portion of the catheter—in one embodiment, thesealing structure is configured to sit at the neck of the vascularcondition to help seal the neck of the treatment site, and in anotherembodiment the sealing structure is configured to sit within thevascular condition. In one embodiment, the sealing structure isdetachable.

In one embodiment, the adhesive occlusion system includes a catheter anda braided sealing structure near the distal portion of the catheter.Part of the braided sealing structure is comprised of optical fibers.The optical fibers link to a light source. Light-activated adhesive isdelivered through the catheter to a treatment site. In one embodimentthe braided sealing structure—comprising one or more optical fibers aspart of the braid—sits near the neck of the treatment site and causesthe light-activated adhesive to harden upon exposure to light; inanother embodiment the braided sealing structure which includes one ormore optical fibers sits within the treatment site. In some embodiments,the braided sealing structure can optionally be detached before thecatheter is withdrawn from the treatment site.

In one embodiment, the adhesive occlusion system includes a catheter anda braided occlusive structure near the distal portion of the catheter.Part of the braided occlusive structure is comprised of optical fibers.The optical fibers link to a light source. Light-activated adhesive isdelivered through the catheter to a treatment site. The braidedocclusive structure—comprising one or more optical fibers as part of thebraid—sits within the treatment site and causes the light-activatedadhesive to harden upon exposure to light. In some embodiments, thebraided occlusive structure can optionally be detached to occlude thetarget space before the catheter is withdrawn from the treatment site.

In one embodiment, the adhesive occlusion system includes an occlusiveimplant and a catheter. Part of the occlusive implant is comprised ofoptical fibers which are linked to a light source. The light-activatedadhesive is first delivered to the treatment site, followed by thelight-emitting occlusive implant. The light-activated adhesive hardensdue to exposure to the light-emitting occlusive implant.

In one embodiment, the adhesive occlusion system includes a catheterwhich delivers light-curable adhesive and a light to activate thelight-curable adhesive. In one embodiment, the light is placed on anexternal surface of the catheter. In another embodiment, the light isplaced within a distal portion of the catheter. In another embodiment,the light is connected to a pusher member which is pushed through thecatheter. The light includes an energy transmitting medium which can beplaced externally or internally relative to the catheter. In oneembodiment, the energy transmitting medium is a structural coil used toprovide rigidity and strength to the catheter.

In one embodiment, an adhesive occlusion system includes a catheterhaving a radially expandable retention structure and an inflatableballoon that expands distally of the retention structure. The retentionstructure can be composed of a mesh braided from a plurality of wiresand heat set to have an expanded configuration (e.g., a concave dish).The balloon can be either pre-coated with a tissue adhesive or can beinflated with a tissue adhesive that escapes from a plurality ofports/apertures near the distal end of the balloon. A detachable jointcan be included to cause separation of the retention structure andballoon from the body of the catheter. In one embodiment, a valve isincluded that, once the catheter is separated, closes to prevent theescape of material proximally from the balloon and into the heart duringan LAA occlusion procedure.

In one embodiment, an adhesive occlusion system includes a catheterhaving an open foam plug at its distal end. The plug may include adistal tether with an anchoring member at its end that secures the plugto tissue. The plug may also be either pre-coated with an adhesive or anadhesive passage within the catheter can be used to deliver the adhesivewithin the plug, so as to weep out to the plug's surface.

In one embodiment, an adhesive occlusion system includes a suctioncatheter that is used to adhere via suction to tissue within a LAA andthen pull the tissue proximally to decrease the size of the LAA cavity.Adhesive delivery tubes are positioned adjacent the suction catheter todeliver adhesive within the LAA. An outer shield catheter may also beused to block of the opening of the LAA during the procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects, features and advantages of which embodiments ofthe invention are capable of will be apparent and elucidated from thefollowing description of embodiments of the present invention, referencebeing made to the accompanying drawings, in which

FIG. 1 illustrates a catheter including a fiber optic member, accordingto one embodiment.

FIG. 2 illustrates a catheter including a fiber optic member, accordingto one embodiment.

FIG. 3 illustrates a catheter including a fiber optic member, accordingto one embodiment.

FIG. 4 illustrates a dual-lumen catheter where one lumen is used todeliver embolic and another lumen contains a fiber optic member,according to one embodiment.

FIG. 5 illustrates a catheter including a sealing structure and a fiberoptic member, according to one embodiment.

FIG. 6 illustrates an embolic coil including a fiber optic member,according to one embodiment.

FIG. 7 illustrates an embolic coil and delivery pusher, according to oneembodiment.

FIG. 8 illustrates an embolic mesh and a delivery pusher, according toone embodiment.

FIG. 9a illustrates a delivery system for an embolic coil including afiber optic member, according to one embodiment.

FIG. 9b illustrates a delivery system for an embolic coil including afiber optic member, according to one embodiment.

FIG. 9c illustrates a delivery system for an embolic coil including afiber optic member, according to one embodiment.

FIG. 10 illustrates a pusher with a light element, according to oneembodiment.

FIG. 11 illustrates a pusher with a light element, according to oneembodiment.

FIG. 12 illustrates a catheter with a light element, according to oneembodiment.

FIG. 13 illustrates a catheter with a light element embedded within thewall of the catheter, according to one embodiment.

FIG. 14 illustrates a catheter with a light element, according to oneembodiment.

FIG. 15 illustrates a catheter with a light element, according to oneembodiment.

FIG. 16 illustrates a catheter with a blocking element, according to oneembodiment.

FIG. 17 illustrates a blocking element, according to one embodiment.

FIG. 18 illustrates a catheter with a retention structure and a balloon,according to one embodiment.

FIG. 19 illustrates a catheter with a retention structure and a balloon,according to one embodiment.

FIG. 20 illustrates a catheter with a retention structure and a balloon,according to one embodiment.

FIG. 21 illustrates a detachable joint, according to one embodiment.

FIG. 22 illustrates an occlusion balloon, according to one embodiment.

FIG. 23 illustrates an occlusion balloon, according to one embodiment.

FIG. 24 illustrates an occlusion balloon, according to one embodiment.

FIG. 25 illustrates a catheter with a retention structure and a balloon,according to one embodiment.

FIG. 26 illustrates a detachable joint with a valve, according to oneembodiment.

FIG. 27 illustrates a catheter with a foam plug, according to oneembodiment.

FIG. 28 illustrates a catheter with a foam plug, according to oneembodiment.

FIG. 29 illustrates a catheter with a foam plug, according to oneembodiment.

FIG. 30 illustrates a suction and adhesive-delivering catheter,according to one embodiment.

FIG. 31 illustrates a suction and adhesive-delivering catheter,according to one embodiment.

FIG. 32 illustrates a suction and adhesive-delivering catheter,according to one embodiment.

FIG. 33 illustrates an occlusion balloon, according to one embodiment.

FIG. 34 illustrates an occlusion balloon, according to one embodiment.

FIG. 35 illustrates a catheter with an occlusion device, according toone embodiment.

FIG. 36 illustrates a catheter with an occlusion device, according toone embodiment.

FIG. 37 illustrates a detachable joint for an occlusion device,according to one embodiment.

FIG. 38 illustrates a detachable joint for an occlusion device,according to one embodiment.

DESCRIPTION OF EMBODIMENTS

Specific embodiments of the invention will now be described withreference to the accompanying drawings. This invention may, however, beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein; rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of the invention to those skilled in the art. Theterminology used in the detailed description of the embodimentsillustrated in the accompanying drawings is not intended to be limitingof the invention. In the drawings, like numbers refer to like elements.

It should be explicitly noted that while numerous different specificembodiments are described herein, features, elements, and functionalityof each can be incorporated into other embodiments shown. In otherwords, elements of the various embodiments are not intended to only beused with that specific embodiment, but can be “mixed-and-matched” withany of the other embodiments shown.

Occlusion is one technique used to address a number of intravascularissues, for example aneurysms and LAAs. With aneurysms, there is anabnormal bulging of a vessel wall and the rupture of the wall could leadto complications including stroke and death. Occlusion involves using afilling structure to either fill the intravascular structure or blockflow to the intravascular structure (e.g., aneurysm) to cut off bloodflow to the target region and prevent rupture. Currently, occlusiongenerally involves the use of embolic devices such as embolic coils tofill the structure. The use of embolic coils is problematic in twosenses—the first is preventing coil migration where coils can migrateelsewhere and create a stroke risk elsewhere, and the second is creatinga thrombogenic mass which sufficiently occludes the target region.

With LAAs, occlusion is particularly problematic. The LAA is a smallear-shaped sac in the muscle wall of the left atrium. For people withatrial fibrillation or irregular heartbeat, the heart impulse isirregular which can cause blood to collect in the LAA and clot overtime. These clots can later migrate out of the LAA causing strokes.Presently, occlusion is one technique to treat this issue, and involvesdelivering an implant device within the LAA. However, designing anappropriate implant is difficult since the region is highly volatile andsubject to high pulsation pressure due to its close proximity to theheart. To maximize anchoring force, these devices typically have barbsor other anchor mechanisms that penetrate the LAA tissue to maintain theposition of the implant. However, these barbs cause tissue damage andeven perforation, which can be undesirable for heart tissue.

Liquid embolics are a type of biocompatible glue which are delivered ina liquid form and harden within the vasculature to form a solidifiedmass and occlude a treatment site. Liquid embolics are currently usedfor a certain set of procedures, such as AVM (arterio-venousmalformation) occlusion. It is difficult to use liquid embolics for awide range of occlusive purposes, such as occluding aneurysms, sincethere is a risk of the embolic mass migrating prior tosolidification—which could introduce additional risks such as stroke.

Tissue adhesives are adhesives which are delivered as a liquid or geland solidify to bind tissue; tissue adhesives are often used forpurposes such as wound repair and sealing vessel punctures. Oneadvantage of tissue adhesives is that, unlike liquid embolic, tissueadhesives bind to the tissue itself thus forming a very firm occlusivemass which is unlikely to migrate. However, tissue adhesives aredifficult to use for intravascular application since the adhesives caneasily solidify prior to delivery, for example while being deliveredthrough a delivery catheter. The ability for the adhesives to adhere tovessel tissue as well as occlude a treatment site means these adhesivescan potentially be used for occlusive purposes—provided there is a wayto control when solidification occurs and/or the location of theadhesives after delivery within the patient until solidification occurs.Various intravascular occlusive purposes could include, for example,aneurysms, atrial septal defects, patent foramen ovale, left atrialappendage occlusion (LAA), patent ductus arteriosus, fistula,arterio-venous malformations, fallopian tube occlusion for the purposesof sterilization, and occlusion in the peripheral vasculature where theadherence to vessel tissue augments the occlusive effect of theseadhesives and makes it more likely the adhesive composition will staywithin the target site and not migrate.

Recent advancements in tissue adhesives have seen the development oflight-curable adhesives. Light-curable adhesives are adhesives which aredelivered as a liquid or gel. Light-curable adhesives can go by a numberof names, including HLAA (hydrophobic light-activated adhesive). Thecompositions include a photo-initiator element which reacts with theadhesive upon exposure to certain frequencies of light. Once exposed tolight of a particular frequency range, constituent elements of thetissue-adhesive composition cross-link, resulting in a hardenedcomposition which also adheres to tissue. These compositions can bethought of as photopolymers which change properties when exposed tolight, here exposure to light causes cross-linking which results in thehardening of the adhesive composition. This property change can occurbased on exposure to different frequencies of light, such as, in oneexample, UV light within a particular UV frequency range. These adhesivecompositions are also generally hydrophobic and thus resist beingdisplaced by blood. US20140348896 and WO15144898 disclose UV-curableadhesives and are hereby incorporated by reference in their entirety.PGSA (polyglycerol sebacate acrylate) is one such material that can beused as a biocompatible adhesive, it can be combined with aphoto-initiator to create a hydrophobic light-activated adhesive gelwhich cross-links and hardens upon exposure to light.

Light-curable tissue adhesives are easily used for external orsuperficial wound repair since the light can easily be delivered toexternal wounds. However, when used within the vasculature,light-curable tissue adhesives can be pragmatically difficult to usesince the tissue adhesive must first be delivered to the treatment siteand then a light source must also be navigated to the treatment site.There could be a significant time lag between the placement of alight-curable tissue adhesive and the delivery of a curing light source,which could cause the tissue adhesive to migrate in the interim. Theembodiments presented herein solve this problem by providing immediatelight exposure to light-curable tissue adhesives, thereby allowing thetissue adhesives to solidify rapidly and create a firm occlusive masswhich binds to tissue and can be used for a variety of intravascularocclusive purposes. In some embodiments, a delivery catheter used todeliver the light-curable adhesive also includes the light to cure saidadhesive. In other embodiments, embolic devices which are deliveredalong with the light-curable adhesives also include the light to curesaid adhesive.

When discussing light-curable adhesives, the adhesives are configured tocure based on exposure to particular frequencies of light. Thespecification will discuss light sources used within an adhesivedelivery system, the light sources should be understood as sittingwithin an appropriate frequency range to cause curing of thelight-activated adhesive. For instance, some adhesives are UV-curablewhere exposure to UV light within a particular frequency range willcause curing. The adhesive delivery system will, in turn, use a UV lightwhich emits light within the particular frequency range to thus cure thelight-activated adhesive. Alternatively, some adhesives cure or hardenin response to exposure to a particular frequency range of “blue” light.The adhesive delivery system will, in turn, use a blue light within aparticular frequency range to cure the light-activated adhesive. Pleasenote, the curing effect is based on the chemical composition of theadhesive, so different frequency/color lights can also be used to affectcuring of the adhesive.

FIG. 1 shows an occlusive adhesive delivery system according to oneembodiment, which includes a catheter 110. The catheter 110 includes anopen lumen spanning the length of catheter 110, and the catheter lumenis used to deliver light-curable adhesive as well as other optionaladditional embolic agents/devices. A cable 112, in one example a fiberoptic cable and in another example an optical fiber, is wound and fixedto an outside surface of the catheter 110. A light source is attached tothe proximal end of the cable; the light generated by the light sourceis conveyed through the cable to the distal end of the cable (e.g., to alens 113) which sits at the distal end of the catheter. When thelight-curable adhesive is delivered, it immediately reacts with thelight from the fiber optic cable or optical fiber and quickly hardens.

Please note the specification may alternately refer to optical fibers,fiber optics, fiber optic cables. Optical fibers are generally theactual fibers that convey light. Fiber optic cables are bundles of theseoptical fibers placed within a cable. These terms, within the concept ofthe specification, can be used synonymously and broadly to refer to allthe concepts. Thus, the term optical fiber should also envelop fiberoptic cables. The term fiber optic cable should envelop optical fibers.The term fiber optic member can also be used to refer to both fiberoptic cables and optical fibers. Other light-transmitting means are alsopossible, besides optical fibers and fiber optic cables and can be usedwith the principles espoused within.

One advantage of using an optical fiber or fiber optic cable to transmitlight from a proximal light source is ease of design. A light sourceplaced at the distal end of the catheter would require a proximalbattery, and at least two wires which span the length of the catheter toconnect the polarized terminals of the battery to the light source. Onthe other hand, with an optical fiber or fiber optic cable, a proximalassembly could contain the light source, and the fiber or cable wouldtransmit the light to the distal end of the system. Since one opticalfiber or one cable bundle could be used to transmit the light, just onefiber or cable could be used instead of two separate wires. In addition,where wires are used to convey electrons within a circuit path from aproximal battery to a distal light source, the degradation of a wirecompletely destroys the circuit and would cause the distal light tofail. With, for example, a fiber optic cable comprising a plurality ofoptical fibers, the failure of one optical fiber will still allow lightto transmit since other optical fibers can still transmit the light.

Different embodiments can utilize the fiber optic cable or optical fiberin different locations of the catheter, for example the tubular wall ofthe catheter can contain the fiber optic cable or optical fiber. Coilsor braids are often used to provide structural support and rigidity tocatheters so they can be pushed through tortuous anatomy withoutkinking. The cable/fiber could be incorporated as part of the one ormore coils and/or braids used to provide structural support to thecatheter. Additionally, multiple cables/fibers could be used with one ormore light sources to further augment the illumination at the distal endof the system.

FIGS. 2-3 shows an adhesive delivery system according to anotherembodiment, the system includes a catheter 110 where the cable 114 ishoused within the catheter, here shown at the bottom of catheter 110(although cable 114 could be placed anywhere within catheter 110). Cable114 could also be wound around the inner lumen of catheter 110. In thisembodiment, appropriate shielding would need to be placed around thecable to prevent the light from illuminating within the catheter whichcould cause premature curing as the light-activated embolic is deliveredthrough the catheter—for instance, a blackened cable housing oradditional cable shielding/cladding could be used to preventillumination within the catheter. Higher frequencies of light could alsocontribute to heat generation, so shielding or cladding could also beused to limit heat dissipation within the catheter. Alternatively, cable114 could be placed within the wall of catheter 110—in one example acable sits longitudinally straight within this wall region, in anotherexample the cable is coiled within this wall region (e.g., similar tothe coiled shape of cable 112 in FIG. 1).

FIG. 4 shows a catheter 110 according to another embodiment where thecatheter 110 includes two lumens 116, 118. One lumen (e.g. lumen 116) isused to deliver the light-activated adhesive as well as other embolicmaterial, while the other lumen (e.g. lumen 118) contains the cableconnecting to the light source. Since early exposure to light isundesirable, a blackened cable housing or additional cableshielding/cladding could be used around the optical fibers or fiberoptic cable to prevent the light-curable adhesive from being illuminatedor otherwise exposed to heat during delivery through the catheter.

In one embodiment, the proximal end of the occlusive delivery systemwould contain a user control interface. The user control interface wouldinclude a light source, an optical fiber or fiber optic cable linked tothe light source, and an energy source such as a battery to power thelight and optionally power other necessary functions. The user interfacewould contain appropriate circuitry so the user could interact with theuser control interface (i.e. push a button) to cause the light to lightup. In other embodiments, the light at the proximal end of the systemcontinuously shines and the cable would transmit the light, so the lightwould continuously shine at the distal end of the delivery system. Thecable or optical fibers should be thought of as an energy transmittingmeans to convey energy from the light source to the distal end of thedevice.

FIG. 5 shows another embodiment of an adhesive occlusive delivery systemwhich includes a catheter 110 and a sealing structure 120 at the distalregion of the catheter. In one embodiment, sealing structure 120 can beused as a neck seal which sits at the neck, opening, or ostium of thevascular condition (e.g. neck of aneurysm), where the sealing structure120 would help ensure delivered embolic material does not seep out ofthe target region. In another embodiment, sealing structure 120 can bephysically placed within the treatment site (e.g. aneurysm) and used tohelp ensure delivered embolic material does not seep out of the targetregion. The width of sealing structure 120 and its position relative tothe distal end of catheter 110 are a couple of variables that wouldimpact whether sealing structure 120 would function as a neck seal, orbe placed within the treatment site.

Sealing structure 120 can be a wire or braid mesh comprised of one ormore metallic wires. A fiber optic cable or optical fiber 122, similarto cable 112 shown in FIG. 1 spans the length of the catheter andcontinues into sealing structure 120 to define one of the constituteelements comprising the braid—in other words, the braid forming sealingstructure 120 would comprise metallic wires as well as cables or opticalfibers. Similar to the embodiment shown in FIG. 1 and discussed earlier,cable 122 can be incorporated as part of a coil or braid spanning thelength of catheter 110 used for structural support of the catheter.Cable 122 continues into the sealing structure 120 mesh, and cable 122in turn is one of the constituent wire elements making up the seal mesh.In one example, sealing structure 120 is a mesh composed of nitinolwires, and optionally can include radiopaque wires as well (i.e.platinum, platinum, or gold) to aid in visualization during theintravascular procedure. Cable 122 could thus be considered anotherconstituent element of the mesh, along with the nitinol wires andoptional radiopaque wires. Cable 122, as described earlier, is connectedto a proximal light source and the light is conveyed through the cableto the distal end of the cable. Since the distal end of cable 122 ispart of the sealing structure 120, the sealing structure 120 would inturn illuminate. Similar to the description above, the light source caneither consistently emit light, or the user could take some action (i.e.press a button on a user interface) to cause the light source to lightup when desired.

In one embodiment, sealing structure 120 is detachable. Thermal,mechanical, or electrolytic detachment means which are well known in theart be placed at the proximal end of the sealing structure 120 wheresaid sealing structure 120 is connected to catheter 110. The userinterface described earlier can also contain appropriate circuitry andan interface (i.e. button) to effect detachment of the sealing structure120. In one example, a light-activated adhesive is delivered through thecatheter to a target treatment site (i.e. an aneurysm or AVM).Additional embolic agents such as embolic coils or embolic meshes analso be delivered through the catheter into the target treatment site.Where the light is selectively emitted, the user can take an action(i.e. press a button) to cause the light to emit light, and the light isconveyed to the distal end of the device. Where the light is constantlyemitted, the light will be consistently conveyed to the distal end ofthe device without any action needed. Exposure to the light will causethe light-activated adhesive to harden and thus occlude the target site.Sealing structure 120 can then optionally be detached to keep theembolic mass (the solidified adhesive, and any additional embolic agentssuch as embolic coils/embolic meshes) within the aneurysm.Alternatively, sealing structure 120 is not detached and the occlusivemass caused by the hardened adhesive and any additional embolic agents(e.g. embolic coils and/or embolic meshes) will fill the treatment sitewithout dissipation, where catheter 110 and the associated sealingstructure 120 are removed once it is confirmed that a sufficient embolicmass has formed. Detachability of sealing structure 120 is only apossible feature of the system and should not be considered necessarysince the embolic formation should take place rather quickly once thelight-curable adhesive is exposed to light.

In some embodiments, sealing structure 120 could function like anocclusive agent. Catheter 110 is placed within the treatment site, sothat sealing structure 120 shown in FIG. 5 also sits within thetreatment site (e.g. aneurysm). Light-curable adhesive delivered fromthe catheter reacts with the light emanating from the optical fibers inelement 120 and hardens. The sealing structure 120 can then optionallybe detached and catheter 110 can be withdrawn. Thus, sealing structure120 would, in this case, act like an occluding agent rather than a neckseal since it's placed and detached within the aneurysm.

The light-activated adhesive is delivered as a liquid or gel via asyringe at the proximal end of the system, where the adhesive isdelivered through the catheter 110. Catheter 110 is navigated throughthe vasculature to the target treatment location. The light-activatedadhesive is then delivered via syringe, through the catheter, and to thetarget treatment location. The light-activated adhesive is then exposedto light and cures or hardens, thus occluding the treatment site.Additional embolic agents (e.g. embolic coils) can also be optionallydelivered through the catheter either before or after delivery of thelight-activated adhesive.

A balloon can optionally be placed near the treatment site to preventadhesive dissipation prior to solidification due to light exposure. Forexample, where the light-curing adhesive is used to treat an aneurysm, aballoon can be placed across the neck of the aneurysm to prevent embolicdissipation before the embolic hardens. Catheter 110 would first beplaced into the aneurysm, and a balloon would be placed and inflatedunder the neck of the aneurysm to seal the space, so adhesive cannotmigrate out of the aneurysm prior to solidifying. This may be desirablewhere there might be a lag between the time that the light-sensitiveadhesive is introduced into the treatment site and the time that theadhesive is exposed to light causing it to solidify. Sealing structure120 would help keep the adhesive in the treatment site and keep it frommigrating elsewhere. Other devices such as stents could also be usedinstead of a balloon, however, the stent should have a relatively tightbarrier layer to help prevent dissipation of the adhesive and theadhesive should have relatively quick exposure to the curing light inorder to prevent adhesive migration prior to solidification.

In other embodiments which will now be discussed, an occlusive implantfunctions as the light source to activate the light-curable adhesive.Occlusive implants such as embolic coils are currently used forocclusive purposes, the coils adopt various shapes upon delivery andfill the treatment site (i.e. aneurysm). In the embodiments of thepresent invention utilizing an occlusive implant as a light source, alight-activated adhesive is initially delivered through a catheter.After delivery, a light-emitting occlusive implant is delivered to thetarget treatment site. The adhesive hardens after being exposed to thelight-emitting occlusive implant and the occlusive implant and hardenedadhesive then comprise the occlusive formation which occludes the targettreatment site. A balloon or stent can optionally be placed near thetreatment site (i.e. under the neck of an aneurysm) to prevent adhesiveand other embolic agents from flowing out of the treatment site beforehardening.

FIG. 6 shows an embodiment of a light-emitting occlusive implant, shownas an embolic coil 124. Embolic coil 124 can be made of variousmaterials including polymer, platinum, platinum-tungsten, nitinol,stainless steel, cobalt chromium, or combinations therein. Embolic coil124 includes a fiber optic element 126, in the figure the fiber opticcomponent is shown as being tied along various loops of the coil so thatthe fiber optic component is substantially taut and sits in the lumendefined by the coiled lumen of the coil. The fiber optic component 126can also be helically wound around the surface of the coil.

The occlusive implant could also adopt other configurations in differentembodiments, in lieu of embolic coil 124. In one embodiment, thelight-emitting occlusive implant could be a braided mesh where the meshis comprised of various metallic wires—for instance, nitinol andplatinum wires. Intrasaccular devices are devices which conform to theshape of the treatment region (e.g. aneurysm) and are often composed ofsoft occlusive meshes which are highly conformable so as to adopt to theshape of the target region. Occlusive meshes and intrasaccular devicesare described in US20140200647, which is hereby incorporated byreference in its entirety. In these embodiments, the light emittingocclusive mesh could be thought of as an intrasaccular device. Anoptical fiber is also included in the mesh in order to allow the mesh toemit light.

Occlusive implants typically include a pusher element used to push theocclusive device through the catheter, and a severing means used tosever the occlusive implant from the pusher and deposit the occlusiveimplant within the target space. Mechanical, thermal, and electrolyticmeans are typically used to sever the occlusive implant from the pusher.An attachment component such as a degradable linkage (i.e. tether oradhesive) can connect between the occlusive device and the pusher, anddegradation of this linkage allows the occlusive device to detach fromthe pusher. US20100269204, US20110301686, US20150289879 all describethermal detachment systems and are hereby incorporated by reference intheir entirety as examples of thermal detachment systems that could beused to detach the occlusive implant from the pusher.

FIGS. 7-8 show a pusher 128 connected either to an embolic coil 124 oran embolic mesh 130. The embolic coil or embolic mesh includes anoptical fiber member (not shown). The inclusion of the optical fiber aspart of the embolic coil or embolic mesh was discussed earlier. Theoptical fiber member would allow the embolic coil or mesh to be lit, asdiscussed earlier.

The principle of the concepts discussed and described so far in FIGS.6-8 is that the occlusive devices should be lit so that when theocclusive device is delivered to the treatment site, the light from theocclusive device reacts with the light-curable adhesive and causes theadhesive to solidify. FIG. 9a illustrates such an embodiment. A pushersystem 132 is used to deliver an embolic coil 140. A heater coil 136 isplaced near the distal end of the pusher, and a severable tether 134extends within the heater coil. A hypotube element 138 sits distal ofthe heater coil and includes a light element 144. An embolic coil 140sits distal of hypotube structure 138 and the embolic coil includes anoptical fiber component 142. The optical fiber component 142 can bewound around the embolic coil (as represented in FIG. 9) or can be tiedwithin and along the length of the embolic coil. Light element 144 sitsproximal of optical fiber 142 and when the light element is lit, lightpasses through optical fiber 142 and is emitted at the distal end ofoptical fiber 142. Hypotube element 138 can be coated to reducedissipation of the light and/or be made of a material to maximizereflection and minimize absorption so most of the generated light ispassed to the optical fiber. A user interface 146 is at the proximal endof the system and includes voltage sources (shown as batteries 148).FIG. 9 shows two batteries, where one battery powers the heater coil 136and another battery powers light element 144—however other variationscould utilize one battery with a parallel circuit structure to powerboth the heater coil and light element. The user interface would includea means (i.e. one or more buttons) for the user to activate the heatercoil and/or the light element. Heating the heater element 136 will severtether 134, detaching the embolic coil 140. So, for example, the usercould press a button to complete the circuit to send an impulse to theheater coil, which heats the heater coil, and results in tether 134severing. Light element 144, in one embodiment, can be consistently litmeaning the optical fiber is continuously lit. In another embodiment,the user could press a button to light the light element to cause theoptical fiber to pass and emit the light. In the embodiment of FIG. 9a ,the light 144 would cease to function once the embolic coil 140 isdetached, so in practice the user would push the lit coil out of thedistal end of the catheter and use the illuminated coil to cure theadhesive. The user could then optionally detach the embolic coil wherethe embolic coil would also function as an occlusive implant, however,once the embolic coil is detached it would cease to emit light.

A variation of this embodiment is shown in FIG. 9b , here the maindifference is that the user interface 146 includes a light 144. Theproximal end of pusher member 132 can be placed within the userinterface to establish electrical communication between the pusher 132and the user interface 146. The pusher includes an optical fiber orfiber optic cable 142, in one example cable 142 sits within the interiorof the pusher as shown in FIG. 9b and in another example the cable iswound around the periphery of pusher 132. Cable 142 traverses past thepusher and is either wound around the surface of embolic coil 140 ortied to embolic coil 140. When the proximal end of pusher 132 isconnected to user interface 146, the light from the user interface 146is transmitted through cable 142 to embolic coil 140 to light theembolic coil. A sacrificial joint 149 is located between the pusher 132and embolic coil 142 and can be degraded via thermal, mechanical, orelectrolytic means in order to sever the embolic coil 142 from pusher132 in order to deliver said embolic coil 142.

FIG. 9c shows another variation of this embodiment, utilizing a light144 within pusher 132, where the light within the pusher conveys lightto the optical fiber component 142 to light the embolic coil 140.

In one embodiment, light-activated adhesive would first be deliveredthrough the catheter. The embolic coil delivered from pusher 132 is thendelivered through the catheter. When the light element 144 is lit, andthe embolic coil sits near the distal end of the catheter or is pushedout of the distal end of the catheter, the light reacts with thelight-activated adhesive to cause it to harden. The embolic coil can bepushed completely out of the catheter so the distal end of pusher 132 isflush near the distal end of the catheter. The user can then detach theembolic coil by activating heater 136 to sever tether 134, detaching thecoil within the target treatment site. Note that once the coil isdetached, the optical fiber is no longer emitting light since theoptical fiber ferries light generated from light element 144, so oncethe embolic coil is detached from the pusher (which also detaches itfrom hypotube 138 which contains pusher light element 144), there is noconnection between the coil/optical fiber and light element 144. Inother embodiments, the optical fiber containing embolic coil can solelybe used to harden the light-activated adhesive, so the user could justuse the light from the optical fiber to react with the adhesive but notdetach the coil. Thus, the coil could be placed flush or external to thedistal tip of the catheter, and used to cure the adhesive, and then bewithdrawn without being detached.

Other embodiments could utilize a dual-lumen catheter system, like thedual-lumen system showed in FIG. 4 where a first lumen (e.g. lumen 116)is used to deliver a light-emitting occlusive coil and a second lumen(e.g. lumen 118) is used to deliver a light-curable adhesive. Adual-lumen catheter system would allow a light-emitting occlusive coilto be delivered prior to a light-curable adhesive such that thelight-curable adhesive is immediately cured upon delivery. In oneembodiment, a light-emitting occlusive coil is pushed past the distalend of a first lumen of the catheter but not detached—such that theocclusive coil is still connected to the pusher. A light-curableadhesive is then delivered through a second lumen of the catheter, theadhesive is exposed to the light-emitting occlusive coil which cures theadhesive upon delivery. The occlusive coil could then optionally besubsequently detached.

Other embodiments could utilize a pusher member with a light at thedistal end of the pusher member used to cure the light-activatedadhesive. In these embodiments, the light-activated adhesive would firstbe delivered through the catheter. A pusher with a light at the distalend of the pusher would then be tracked through and past the distal endof the catheter, and the light reacts with the adhesive to cure andharden it. This is shown in FIGS. 10-11 where a pusher 151 is trackedthrough a catheter 150 and pusher 151 has a light element 152 at itsdistal end. The light element is pushed outside of the catheter andreacts with the light-adhesive. The light source has a voltage source topower it, shown as a battery 148 and the pusher can contain theappropriate wiring to connect the battery and the light element. Otherembodiments could utilize a dual-lumen catheter as shown in FIG. 4 wherea first lumen is used to deliver a light-activated adhesive and a secondlumen is used to deliver the pusher member with distal light. Theadvantage of a dual lumen system is that the pusher could bepre-delivered to the distal tip of the catheter, and the light-activatedadhesive would immediately react and cure due to exposure to the lightupon delivery—mitigating the risk of the adhesive dissipating prior tosolidification and possibly avoiding the need to use a balloon aroundthe target treatment site (e.g. under the neck of an aneurysm) toprevent adhesive dissipation prior to solidification.

FIG. 12 shows another embodiment of an adhesive delivery system where alight can be mounted to the catheter itself, and the light is used tocure light-activated adhesive. The previous embodiments utilized aproximal light source and a fiber optic member to deliver the light to adistal region of the catheter—in contrast, the embodiment of FIG. 12utilizes a light source 154 placed in a distal region of the catheter158. The light-activated adhesive is delivered through the catheter andreacts with the catheter-mounted light to cure and harden the adhesive.Instead of wiring connecting to the light source, a metallic coil ormetallic braid 156 which is used to provide structural rigidity andsupport to the catheter can also be used to ferry current to the lightsource. In this embodiment, two coil elements (one supply, one return)can be used. Alternatively, one coil element can be used (i.e. for thesupply) and the blood itself can comprise the ground to complete thecircuit to power the light. The coil(s) could be placed externally ofthe catheter tubing (as shown), or be placed within the wall of thecatheter tubing. In alternative configurations, similar concepts toFIGS. 2-4 could be used where one or more wires are placed within thecatheter to power the light, or a multi-lumen catheter which includes aseparate lumen for the wires powering the light could also be used. Inthese configurations all the circuitry would be within the catheter, butthe light would be mounted externally of the catheter. Alternativeconfigurations could utilize a thin or small-profile light which sitswithin the catheter—the light should be small enough to not block thecatheter lumen, however the light should be radiant enough to cure thelight-activated adhesive. Other configurations could utilize multiplelights. A proximal user interface connecting the wires or coilcomponents could utilize a battery to power the device, and apush-button to toggle the light on or off.

FIG. 13 shows another embodiment utilizing a light 164 where the lightis integrated into the wall 162 of a catheter. The catheter contains alumen 160 used to deliver the light-curable adhesive, and the adhesiveis exposed to the light 164 upon delivery and cures. Other embodimentscould utilize a proximal light source and an optical fiber or fiberoptic cable placed within the wall of the catheter, where the distal endof the fiber optic component is exposed to cure the adhesive. Otherembodiments could utilize multiple lights within wall region 162 ormultiple optical fibers/fiber optic cables within wall region 162.

The following embodiments would be useful for treating a variety ofvascular conditions but have special utility in treating left atrialappendage (LAA) as well as some types of aneurysms. An LAA is a smallear-shaped sac in the muscle wall of the left atrium, patients withatrial fibrillation or irregular heartbeat are at risk of clots formingin the LAA which can cause complications such as stroke if these clotsare pumped out of the heart and migrate elsewhere. Occlusion of the LAAis one technique that is practiced to prevent this situation forpatients with irregular heartbeat or atrial fibrillation. LAA's canadopt awkward, complex shapes which makes occlusion of the LAAdifficult. Additionally, since the LAA is so close to the heart, theregion is exposed to heavy pulsatile pressure which makes placement andretention of occlusive devices very difficult. Current devices toocclude LAA's typically utilize sharp barbs to help stay affixed withinthe LAA given the complex morphology and pulsatile pressure of the LAAspace, however, these barbs can lead to other complications includebleedout between different vessels. The following embodiments utilize alight-curable adhesive to treat a variety of conditions, in particularaneurysms and LAA. Some of these embodiments utilize a pusher used todeliver a light used to cure a light-activated adhesive, similar to theembodiments shown in FIGS. 10-11.

In one embodiment shown in FIG. 14, a balloon catheter 170 has a distalinflatable balloon 172, inflation lumen 174 to deliver inflationfluid/media to the balloon, and an inner delivery lumen 176 used todeliver light activated adhesive and a delivery pusher 178 with a distallight 180 used to cure the light activated adhesive. Balloon catheter170 would be tracked to the site of the LAA or vascular treatment site,and the distal end of the balloon catheter would be placed within thetreatment site or at the neck of the treatment site. Balloon 172 is thenexpanded to seal the area adjacent to the neck of the treatment site toprevent any delivered embolic material from escaping. Alternatively, ifthe neck is large enough the balloon can physically placed within theneck of the LAA or vascular treatment site and expanded. Light-activatedadhesive is delivered through delivery lumen 176 and delivery pusher 178is subsequently delivered through the delivery lumen so that the distalend of delivery pusher 178 including light 180 are past the end of thedelivery lumen. Delivery pusher 178 contains the appropriate battery andcircuitry to light the light 180 (or alternatively, a proximal interfacecontaining a battery can connect to the proximal end of delivery pusher178). The light emitted from light 180 reacts with the light-activatedadhesive already in the LAA/treatment site. Though there may be a lagbetween the time of the delivery of the light and the adhesive since thesame delivery lumen 176 is used for both, the balloon prevents any ofthe adhesive from migrating in the interim. In one embodiment, deliverypusher 178 could utilize various mechanical, electrolytic, or thermaldetachment systems well known in the art to detach the light 180 frompusher 178. In one embodiment, a dual-lumen balloon catheter could beused (similar to the dual-lumen concept of FIG. 4, except used with aballoon catheter) so that one lumen is used to deliver adhesive andanother separate lumen is used for the delivery pusher. One advantage ofa dual-lumen system is rapid curing since the delivery pusher 176 couldbe pre-delivered to the distal tip of its own lumen and the adhesivecould be delivered through a separate lumen—however, the presence ofballoon 172 mitigates many of these issues since the balloon preventsthe adhesive from escaping between the time the adhesive is deliveredand the time light 180 is delivered.

In another embodiment, shown in FIG. 15, a balloon catheter 171 is usedto deliver light-activated adhesive and the distal tip of the ballooncatheter utilizes an extension 184 and a light 180 at the end of theextension. In this embodiment, there is no need to deliver a separatelight source through lumen 176 since the light source is fixed to thedistal tip of the balloon catheter. The balloon catheter would containthe appropriate circuitry to power the light and a proximal battery orinterface could be used to power the light 180. In one example, a fiberoptic or optical fiber member can be used as a structural reinforcementlayer of the balloon catheter and span the length of the catheter, wherethis fiber optic/optical fiber member is used as the light 180 at thedistal end of the balloon catheter. In one embodiment, extension 184could utilize various detachment means (thermal, electrolytic,mechanical) to detach the light 180.

Additional variations of the balloon catheter concepts of FIGS. 14-15are also possible. For instance, a mesh structure or a metallic frame orprop can be placed proximally adjacent to the balloon to help keep theballoon from contracting during adhesive delivery.

In another embodiment, shown in FIGS. 16-17, a retention structure 192sits near the distal end of a catheter and acts to retain deliveredlight-activated adhesive within the treatment site. Retention structure192 functions similar to sealing structure 120 of FIG. 5—with theexception being that the retention structure does not contain a lightitself. Retention structure 192 can take on a number of configurations,including a mesh braided device or a solid metallic (e.g., nitinol)frame or polymeric structure. Catheter 190 is placed near the treatmentsite so that the retention structure 192 abuts the neck of theLAA/treatment site, or retention structure 192 can sit within the neckif sized appropriately. Adhesive is then delivered through catheterlumen 196 and retention structure 192 keeps the adhesive from escaping.A light source, similar to the light pusher structure 178 of FIG. 14 isthen inserted within the lumen to react with the adhesive. Once theadhesive hardens, catheter 190 and attached retention structure 192 arewithdrawn. In one embodiment, retention structure 192 has a thermal,electrolytic, or mechanical detachment system to detach the retentionstructure from the catheter to leave the retention structure in placeafterwards.

In one embodiment, retention structure 192 can include adhesive atlocation 194 of FIG. 17. The adhesive would be pre-placed on theexterior of retention structure 192 at location 194 and partially orfully exposed to light in order to adopt a gel like or solidifiedconsistency to prevent migration of the adhesive. If the adhesive is ina semi-solidified gel-like state, the exposure to light after deliverywould solidify the adhesive—if the adhesive is already solidified priorto delivery of the retention structure 192 then the adhesive will besolidified when the retention structure is placed within thevasculature. In any event, the presence of the adhesive on the exteriorof the retention structure 192 would seal any gaps between the retentionstructure and the LAA, ensuring that any subsequently delivered adhesivehad no escape path past retention structure 192 prior to the time whenthe adhesive is exposed to light and cures or solidifies.

Please note light-curable adhesives, and systems used with light-curableadhesives were discussed. The chemistry of the adhesive itself willdetermine which frequency range of light will cure or harden theadhesive. In some embodiments, UV-frequency light is used to cure theadhesives and therefore the lights used to cure a UV-light curableadhesive are in the UV frequency range. According to Planck's equation(E=hv), Energy (E) is directly proportional to light frequency (v), suchthat a higher frequency corresponds to higher energy. Ultravioletfrequency light sits on the higher end of the frequency scale, whichcould lead to issues such as heat transmission during delivery. Thespecification discussed how shielding could be used to limit light orenergy transmission away from the optical fiber or energy carryingmedium. Similarly, light in a lower than UV-frequency range (e.g. “blue”or other color light in thered-orange-yellow-blue-indigo-violet-ultraviolet) range could be used tocontrol possible heat transmission issues.

Other embodiments presented herein utilize a conformable structure, suchas a balloon, to conform to part or all of the geometry of the targetocclusive area (e.g. LAA). Adhesive is used along with the conformablestructure to affix the conformable structure within the target occlusivearea, thereby occluding the target area. FIGS. 18-20 illustrate anotherembodiment of an occlusion device 200 utilizing this concept where saidocclusion device 200 can be particularly effective in occluding the leftatrial appendage (LAA) 10 of a patient. Unlike the prior describedembodiments, the device 200 includes both a retention structure 202 andan occlusion balloon 204 that can be used to deliver tissue adhesiveinto the LAA 10. Specifically, the retention structure 202 can be firstexpanded to block off the opening of the LAA 10, and then the balloon204 can be expanded to deliver the tissue adhesives. These upcomingembodiments are primarily described with regard to traditional,non-light activated tissue adhesives. However, light-activated adhesivescould also be used where the delivery system would include a curinglight, similar to the delivery systems described above. Though theseembodiments will be primarily described for use in treating LAA's andhave particular utility in this function, these embodiments can be usedto treat a variety of other vascular conditions including aneurysms,atrial septal defect, fistulas, etc. and have general utility inoccluding space within the vasculature.

The device is primarily comprised of the pusher or catheter body portion208 and the occlusion portion (e.g., the retention structure 202 andballoon 204) that selectively detaches from the catheter body portion208, as seen in FIG. 20. Turning first to the occlusion portion, theretention structure 202 is, in one embodiment, composed of a mesh ofbraided wires that are heat-set to expand, when unconstrained, into apredefined radial shape. For example, FIGS. 18-20 illustrate a retentionstructure 202 with a dish-shaped, concave structure opening in a distaldirection. In another example a device can have a cylindrical,cup-shaped retention structure. The retention structure may also takethe expanded form of a relatively flat disc, an ovoid shape, a sphericalshape, or other variations.

The occlusion balloon 204 is connected distally of the retentionstructure 202 and can be composed of a compliant material to allowunconstrained expansion as volume and pressure increase. For example, ahighly elastic, low durometer urethane can be used. In another example,silicone, PeBax, or a combination of both can be used.

In the embodiment of FIGS. 18-20 and 22, the balloon 204 has a generallyconical shape, terminating with a distal radiopaque marker 204B and aproximal connection member 206. While the balloon 24 will initiallyexpand to the generally conical shape, it may lose this shape and expandto a more rounded shape, depending on the volume of material injectedinto it. In one example, the balloon 204 expands to up to about 18-20 mmdiameter (e.g. at its widest bottom portion) and about 18-35 mm inlength (e.g. from the bottom portion that sits near the neck of the LAAto the top portion that sits near the dome/top of the LAA). Alternately,the balloon can have a generally rounded or oval shape (balloon 205,FIG. 23), two adjacent rounded shapes (balloon 207, FIG. 24), or anyother variation of shapes. These measurements are only proffered by wayof example and can be modified depending on the sizing characteristicsof the LAA/vascular condition.

In one embodiment, the balloon 204 includes a plurality of apertures204A positioned near the balloon's distal end, as best seen in FIG. 22.Once inside the LAA 10, the balloon 204 is inflated or injected withtissue adhesive—in a process that will be explained in more detaillater. The apertures 204A are sized to open as the balloon 204 expandsand to allow the adhesive to leak into the LAA 10 slowly enough to allowthe balloon 204 to fully inflate. Additionally, the distal location ofthe apertures 204A allows the proximal, enlarged portion of the balloon204 to engage and seal the LAA 10 before any of the tissue adhesive canleak out into the heart.

In another embodiment, rather than being injected or inflated withtissue adhesive, the outer surface of the balloon 204 is instead coveredwith tissue adhesive. The balloon 204 is injected with saline, contrastagent, or hydrogel—in a process that will be explained in more detaillater. Once the balloon 204 expands, the outer adhesive coating adheresto the tissue of the LAA 10, sealing the cavity off from the heart.Alternative embodiments can utilize a balloon with channels or poreslinking the inner part of the balloon to the outer part of the balloon.The inner balloon surface, or the channels connecting the inner balloonsurface and outer balloon surface can be coated with tissue adhesive. Asthe balloon is injected or inflated (e.g., with saline, contrast agent,or hydrogel), the tissue adhesive migrates or diffuses to the outersurface of the balloon, thereby adhering to the tissue of the LAA as theballoon expands to contact the interior surface of the LAA.

The tissue adhesive used can include cyanoacrylate or UV-activated glue.In one specific example, the tissue adhesive is n-Butyl Cyanoacrylate(nBCA) and Lipiodol (iodized poppy oil) in about a 9:1 ratio,respectively, and after use, Dextrose can be used to clear out thecatheter 208.

In one embodiment, the occlusion portion can be created by laser weldinga proximal radiopaque marker tube and a distal radiopaque marker tube ona proximal and distal side, respectively, of the mesh retentionstructure 202, creating a passage therethrough. The balloon 204 is thenbonded onto the distal radiopaque marker tube to allow communication ofthe passage within the balloon 204. The proximal radiopaque marker tubeis connected to the proximal connection member 206, which also containsa passage therethrough and is selectively disconnectable from the distalend of the catheter body 208.

The catheter/conduit 208 is a generally elongated tubular structurehaving at least one passage within it that is connected to thepreviously described passage through the occlusion portion. This passageallows for delivery of the tissue adhesive (or saline, contrast,hydrogel, etc.) from a proximal port to the interior of the balloon 204.Additionally, the catheter 208 may have additional passages and features(e.g., UV lamp if a light-activated tissue adhesive is used) as othercatheters described in this specification.

The distal end of the catheter 208 is selectivelyconnectable/disconnectable to the proximal end of the proximalconnection member 206. In one embodiment, the two components are engagedwith each other via mating threads, allowing the catheter 208 to berotated on its axis until the threads disengage. For example, FIG. 21illustrates the catheter body 208 having a reduced-diameter and distallyextending male threaded portion 208B. This threaded portion 208B has athread and diameter sized to engage the recessed, female portion 206A ofthe member 206. Once threaded together, the catheter's passage 208Aconnects to passage 206B of the member 206, which ultimately connects onto the interior of the balloon 204.

In alternate embodiments, different detachment mechanisms can be used.Different detachment mechanisms can be found in U.S. Pat. Nos.8,182,506; 9,561,125; 9,867,622; and 9,877,729; each of which isincorporated herein in their entirety by reference. It should beunderstood that while some of these embodiments incorporated byreference do not include a passage between their pusher/catheter andimplant, such a passage could be included to accommodate the use ofballoon 204.

The detachment mechanism illustrated in FIG. 21 may include a simple,continuous open passage throughout, such that when detachment occurs,the passage 206B is still open to the environment. If the tissueadhesive has hardened/cured, then little or none of it should escapefrom the passage 206B into the heart. However, it may also be desirableto include a valve, such as a check valve or one-way valve, within theproximal connection member 206 (or elsewhere in the occlusion portion)to prevent backflow.

FIG. 26 illustrates one example of a proximal connection member 206 witha valve that remains open when connected to the catheter body 208 butcloses when detachment from the catheter body 208 occurs. An outerhousing 206F is connected to a distal retainer portion 206E on which theretaining portion 202 and balloon 204 are affixed to, and to a threadedfemale insert portion 206D. A valve member 206G with a proximal gasket206C having a center aperture 206J is located between portion 206E and206D. When the male threaded portion 208B (shown in FIG. 21) of thecatheter 208 is threaded into the threaded female insert portion 206D,its distal end presses against the gasket 206C, which in turn pressesagainst the valve member 206G, causing a central slit 206H or passage inthe member 206G to open into passage 2061 in portion 206E, whichultimately opens to the interior of the balloon 204. In this respect, apassage is created between the male threaded portion 208B, throughaperture 206J, through slit 206H, into passage 2061, and finally intothe balloon 204. Once the male threaded portion 208B is removed from thefemale threaded interior of the threaded female insert portion 206D,pressure is removed from the valve member 206G, causing the slit 206H ofthe valve member 206G to close and prevent backflow from the proximalconnection member 206 and into the heart.

Alternately, the valve member 206G can be a one-way valve member. Forexample, the valve member 206G can be a one-way duck-billed valve memberor an umbrella valve member.

Both the catheter body 208 and the occlusion portion (which includesretention structure 202 and balloon 204) can be advanced through alarger delivery or guide sheath/catheter 210 or can be preloaded withinan outer sheath/catheter that can be retracted to release the occlusionportion once located within the LAA 10.

The LAA treatment procedure involves making a septal puncture in theheart under ultrasound/echocardiography, and a larger delivery conduithousing the occlusive device/delivery catheter is advanced through thepuncture. The LAA location and shape is checked under fluoroscopy. Alarger delivery sheath or delivery catheter 210 is pushed into the LAA,and the smaller inner catheter 208 is tracked to a distal portion of theouter sheath. Catheter 210 is withdrawn so as to expose the shieldretention structure and catheter 208 is also retracted, such that theretention element 202 radially expands to circumferentially contact theopening of the LAA 10, as seen in FIG. 18. Proximal displacement of thecatheter 208 as it sits within the LAA during this delivery step willensure that the shield structure is moved proximally to the location ofthe LAA neck as the shield expands, thereby ensuring the shield isproperly seated at the neck or opening of the LAA. The larger deliverysheath 210 can optionally be used to provide a retention force againstthe proximal end of retention element 202 for proper seating.Alternative delivery methods can utilize pushing catheter 208 distallyto expose the shield structure, or retracting outer deliverysheath/catheter 210 when said sheath 210 is positioned near the neck ofthe LAA, however care should be taken to ensure the shield structure isseated properly at the neck of the LAA.

Adhesive (or alternatively—saline, contrast agent, or hydrogel) is theninjected through the proximal end of catheter element 208 (e.g., througha syringe mated to the catheter hub), through its internal passage 208A,through proximal connection member 206, and into balloon 204 to fill theballoon. If adhesive is injected and apertures 204A are present on thedistal end of the balloon 104, the adhesive leaks out into the far endof the LAA 10 as the proximal portion of the balloon 204 radiallyexpands to seal off the opening of the LAA 10, as seen in FIG. 19.Alternately, if no apertures are present, the balloon 204 expands untila layer of adhesive on its outer surface contacts and adheres to thetissue of the LAA 10.

Fluoroscopy can be used to ensure proper curing and stability of theinjected fluid, and proper occlusive positioning of the balloon. Thedelivery sheath 210 is retracted if it is still pinned against theretention structure, and the smaller catheter 208 (which is also used asthe adhesive conduit) is disengaged from the occlusive device (eitherthrough mechanical rotation as outlined earlier, or through thealternative detachment methods presented). The physician can perform afinal echocardiogram and angiogram to verify the proper positioning ofthe occlusive device before inner catheter 208 and outer catheter 210are withdrawn and procedure is terminated.

In an alternative delivery procedure, no outer sheath/catheter 210 isused and instead only the catheter 208 housing the actual occlusivedevice is used. Such an arrangement is feasible, for instance, insituations where the blood vessels may be smaller (e.g., for juvenilepatients).

Alternative occlusion embodiments can utilize an occlusive balloon, butno holes. Instead, the balloon is made of a highly conformable materialwhich conforms to the geometry of the LAA. The balloon is filled with aninflation fluid (e.g., saline, contrast agent, hydrogel, or adhesive).The balloon is optionally further pre-coated with an adhesive substancesuch that the balloon sticks to the occlusive space as the balloonexpands. Alternatively, the balloon is not pre-coated with adhesive andthe filling force provided by the balloon filling agents is sufficientto cause the balloon to stick and conform to the target occlusive space.The check valves described above can also be used to ensure the balloonfilling fluids do not leak out from the balloon through the deliverycatheter/conduit. After the balloon is filled, the delivery catheterconnected to the mesh structure and balloon is detached and withdrawn.In alternative embodiments, the balloon contains channels and anadhesive material is pre-contained within the channels or within theinterior balloon surface in fluid communication with the channels. Asthe balloon expands, the adhesive is pushed out from the balloon to theballoon outer surface and adheres to the vessel wall.

Some embodiments may forego a retention structure entirely. Forinstance, in circumstances where adhesive is not used to fill theballoon (e.g., in embodiments where the balloon is pre-coated with anadhesive on the outer surface, or those embodiments where the balloon isfilled with contrast agent or saline), a retention structure may noteven be necessary since there would be no issues from adhesivepotentially leaking out from the LAA/balloon. FIG. 25 illustratesanother embodiment of a device 212 in line with these principles, thatis similar to the previously described device 200, but lacks retentionstructure 202. In other words, the device 212 only includes a balloon204 that is delivered within a LAA 10 and expanded to cause occlusion.As with the previously described balloon 204, it may include distalapertures 204A that allow tissue adhesive delivered into the balloon 204to escape into the LAA 10. Alternately, the balloon may lack theapertures 204A, be filled with a non-adhesive material (e.g., saline,contrast), and have an adhesive coating on its outer surface that allowsit to adhere to the interior of the LAA 10. As with prior embodiments,the balloon 204 can be detached from the catheter 208 at the proximalconnection member 206.

Some embodiments may forego the use of a balloon and instead utilizealternative filling structures. FIGS. 27 and 28 illustrate anotherembodiment of an occlusion device 220 that is particularly suited fortreatment of a LAA, among other uses, utilizing this principle.Specifically, the occlusion device 220 includes a plug of open cell foam222 fixed to the proximal connection member 206 of the catheter 208. Asbest seen in FIG. 28, the distal end of the plug 222 includes a rigid orsemi-rigid tether 224 that is connected to a distal anchor member 226.The distal anchor member 226 provides a distally facing surface (e.g., acircular plate) that adheres to an interior surface of an LAA 10 tothereby anchor the plug 222 in place. The catheter 208 can be detachedfrom the proximal connection member 206 (e.g., via one of the previouslydescribed detachment mechanisms), leaving the plug 222 within the LAA10. Over time, tissue will grow into the plug 222, fully occluding theLAA 10.

In one embodiment, the anchor member 226 has a distal surface havingtissue adhesive 226A on it. In another embodiment, the distal surfacehas barbs, spikes, or similar penetrating anchoring mechanisms.

In one embodiment, the plug 222 of the device 220 can be pre-coated in atissue adhesive or can be injected with a tissue adhesive (e.g., anadhesive delivering tube can be positioned to open at the proximal endof the plug 222, allowing the adhesive to “weep” out of the plug 222.The device 228 of FIG. 29 illustrates such a plug 222 with an outeradhesive layer 22A, either pre-coated or injected into the plug 222.Additionally, in such an adhesive-coated embodiment 228, the tether 224and anchor member 226 can be omitted.

In any of the embodiments with the open cell foam plug 222, the foam canbe composed of various materials such as starch, chitosan, biodegradableurethanes, biocompatible urethane, and materials that can absorb andcapture blood to enhance swelling.

In some embodiments, suction can be used to collapse the vascularstructure (e.g., LAA) to augment or replace occlusion. FIGS. 30-32illustrate another embodiment of a device 230 for occluding a portion ofa vessel, such as a LAA 10, utilizing this principle. The device 230includes an outer introducer sheath 232 having a distal end that isinitially placed near the opening of the LAA 10. A shield sheath 234,having an enlarged, conical distal end 234A is advanced distally untilthe end 234A contacts and blocks off the opening of the LAA 10, as seenin FIG. 31. Once blocked off, a suction catheter 236 is distallyadvanced out of the shield catheter 234 until its distal end is incontacts with an inner surface of the LAA 10. Suction is then appliedthrough the suction catheter 236, causing the distal end of the catheter236 to be fixed or anchored within the LAA 10. Next, the suctioncatheter 236 is proximally withdrawn towards the shield catheter 234 toreduce the size of the LAA 10, as seen in FIG. 32.

Once the size of the LAA 10 has been reduced, tissue adhesive 239 isinjected to maintain the new size of the LAA 10. In that regard, thedevice 230 further includes a plurality of adhesive delivery tubes 238that terminate at locations around the suction catheter 236 and areconnected to an injectable supply of tissue adhesive 239 at the proximalend of the device. Once the adhesive 239 has been ejected from the tubes238, has filled the LAA 10, and hardened, the device 230 can be removed.

As previously discussed, fluoroscopy is typically used to visualizeocclusion devices for a LAA treatment procedure. In that respect, liquidcontrast agents are often injected into the patient (e.g., into thecatheter and balloon or external of the closure device). However,contrast agents are not always well-tolerated by patients with renaldisease.

FIG. 33 illustrates a balloon 240 that can be used with any of theprior-described embodiments and which is visible under fluoroscopywithout the use of contrast agents or externally injected contrastagents. Specifically, the balloon is composed of a urethane resin with asmall percentage of one or more of the following radiopaque materials:barium sulfate, tungsten, iodine, gold, bismuth trioxide, bismuthsubcarbonate, or bismuth oxy chloride. As seen in FIG. 33, the entireballoon can be composed of this radiopaque material. Alternately, asseen in FIG. 34, the balloon 242 can be composed primarily ofnon-radiopaque material and can further have a plurality of radiopaquestrips 244 composed of the above-mentioned materials that are printed oradhered onto the inner or outer surface of the balloon 242.

Several of the previous embodiments included a retention structuresitting at or near the neck of the vascular treatment site to aid inkeeping the occlusive device within the target area. The followingembodiments utilize a retention structure that has a first elongated,radially compressed shape and a second radially expanded shape, wherethe user can control the shape—advantages of this approach include theability to treat a wide variety of differently sized LAA's and easierdelivery through the outer delivery sheath since the retention structuredoes not automatically take on its fully expanded shape upon delivery.FIGS. 35-38 illustrate another embodiment of an occlusion device 250that can be used for treatment of a LAA, among other uses, in line withthis principle. The device 250 includes an inflatable balloon 204 and anexpandable retention portion 202, similar to previously describedembodiments. However, the device 250 further includes a mechanism foradjusting the diameter of the retention portion 202.

The adjustment mechanism includes an elongated inner core member 252that is positioned in an outer sheath or tubular structure 260. Theproximal portion 252A of the core member 252 extends out the proximalend of the catheter 208 and may optionally include a handle to allow theuser to rotate it relative to the catheter 208. The distal portion ofthe member 252 includes a threaded portion 252B which, as describedbelow, is removable from the proximal portion 252A at the end of aprocedure so as to leave the occlusion portion in the LAA of thepatient.

The retention portion 202 is fixed to a distal collet 254 that ispositioned on the threaded portion 252B and fixed at a longitudinalposition on the threaded portion 252B and can, along with the retentionportion 202, either rotate freely or along with the threaded portion252B. The proximal end of the retention portion 202 abuts proximalcollet 256, which has a thread that is threaded on to the thread of thethreaded portion 252B. If the core member 252 is rotated, all of thecomponents on the distal threaded portion 252B (e.g., collets 254, 256,and retention structure 202) would also rotate and no changes wouldoccur. However, the outer sheath 260 includes an engagement mechanismthat can engage the proximal collet 256, allowing the user to preventthe threaded proximal collet 256 from rotating. In this state, rotatingthe inner core member 252 in a predetermined direction longitudinallymoves the threaded proximal collet 256 in the distal direction. Hence,rotating the inner member 252 can move the proximal collet 256 from theposition in FIG. 35 to the position in FIG. 36, causing the retentionmember 202 to radially increase in size. Depending on how far theproximal collet 256 is moved, the radial size of the retention member202 can be determined by the user, depending on the size of the targetLAA. Once expanded, a passage through the inner member 252 can be usedto deliver adhesive or saline/contrast into the balloon 204 as describedin other embodiments.

The engagement mechanism between the outer sheath 260 and the threadedproximal collet 256 can be best seen in FIGS. 37 and 38, including oneor more tabs 260A (e.g., four positioned at 90 degrees from each other)extending distally from the distal edge of the outer sheath 260. Theouter sheath 260 can be distally advanced relative to the inner member252 (or vice versa), so that the tab 260A engages a mating recess orslot 256D in the proximal collet 256. This engagement causes theproximal collet 256 to rotate with the outer sheath 260, not the innercore member 252. A user can then rotate the core member 252 whileholding the outer sheath 260 in place. Again, in a predetermined firstdirection, the proximal collet 256 will move proximally, causing theretention structure 202 to expand. To prevent accidental engagement ofthe mechanism, a spring 258 is disposed around the proximal portion252A, fixed at its proximal end to outer sheath 260, and abuts thethreaded proximal collet 256. This provides a biasing force to keep thetabs 260A out of engagement with slots 256A.

The above-described engagement mechanism can also be used to causeseparation of the proximal portion 252A from the threaded distal portion252B. As best seen in FIG. 38, the distal threaded portion 252B isscrewed/threaded on to the proximal portion 252A via the female threadedportion 252F and the male threaded portion 252E, respectively.Preferably, the threads of portions 252E and 252F are such that theyunscrew in a second predetermined direction, opposite of the firstpredetermined direction that moved the proximal collet 256 distally.Once separated, the proximal portion 252A and outer sheath 260 can beremoved from the patient, leaving the distal threaded portion 252B andall of the components attached thereto.

Additional variations to the embodiments presented herein are possible.An anti-thrombogenic coating can be used either on the shield retentionstructure, balloon, or both. One such anti-thrombogenic coating that canbe used is described in US Pub. No. 2018/0093019 which is herebyincorporated by reference in its entirety. Endothelial growth factorcoatings can be used to facilitate tissue growth over the device, thecoating can be used on the shield retention structure, balloon, or both.The balloon can have various shapes and surface characteristics toenhance friction and sticking force between the balloon and targettreatment area—for instance, ribs and indentations can be used all alongthe balloon or in select regions of the balloon. The balloon, in someembodiments, can be biodegradable such that the balloon naturallybiodegrades and disappears over time. Various filling materials can beused, as described above, to fill the balloon—for instance saline,contrast agent, hydrogel (degradable or non-degradable), oils, and/oradhesives. In other embodiments, other polymerizing materials (such asliquid embolic, which harden or precipitate in response to bloodexposure) can be used. Some types of liquid embolics which can be usedare disclosed in U.S. Pat. Nos. 9,351,993 and 9,078,950—both of whichare hereby incorporated by reference in their entirety.

The principles and embodiments discussed within the specification havegenerally been discussed for use with light-curable adhesives and tissueadhesives which bind to the vascular tissue itself. These systems canalso be used with light-curable liquid embolics where the liquid embolicsolidifies based on exposure to light. As discussed earlier, thedistinction between embolic and adhesive is that adhesives physicallyadhere to tissue.

Although the invention has been described in terms of particularembodiments and applications, one of ordinary skill in the art, in lightof this teaching, can generate additional embodiments and modificationswithout departing from the spirit of or exceeding the scope of theclaimed invention. Accordingly, it is to be understood that the drawingsand descriptions herein are proffered by way of example to facilitatecomprehension of the invention and should not be construed to limit thescope thereof.

What is claimed is:
 1. An occlusion device for treatment of a medicalcondition, comprising: an elongated conduit having at least one passagebetween its proximal end and distal end; and, an occlusion portiondetachably connected to a distal portion of said conduit; said occlusionportion comprising a radially expandable retention structure and aninflatable balloon positioned distally of said retention structure; saidballoon being in communication with said at least one passage of saidconduit.
 2. The occlusion device of claim 1, wherein said balloon has aplurality of apertures located at its distal end.
 3. The occlusiondevice of claim 2, wherein said balloon is configured to receive atissue adhesive flowing from said proximal end of said conduit, throughsaid at least one passage, into said balloon, and out of said pluralityof apertures.
 4. The occlusion device of claim 1, wherein said radiallyexpandable retention structure is composed of braided mesh that is heatset to form an expanded, concave shape, an open cylindrical shape, or aflat disc shape.
 5. The occlusion device of claim 1, further comprisinga detachment assembly connecting said conduit and said occlusionportion; said detachment assembly comprising a threaded male portionengaged with a threaded female portion, such that rotation of saidconduit detaches said conduit from said occlusion portion.
 6. Theocclusion device of claim 1, wherein said occlusion portion furthercomprises a valve between said at least one passage and an interior ofsaid balloon, such that when said occlusion portion is detached fromsaid conduit, said valve is closed.
 7. The occlusion device of claim 1,wherein an exterior surface of said balloon is coated with tissueadhesive.
 8. The occlusion device of claim 1, wherein said ballooninflates to a generally conical shape.
 9. The occlusion device of claim8, wherein said balloon has a plurality of apertures at a distal end ofsaid conical shape.
 10. An occlusion system for treatment of a medicalcondition, comprising: a conduit having a passage between its proximalend and distal end; an occlusion portion being connected to andselectively detachable from a distal portion of said conduit; saidocclusion portion comprising a retention structure having a radiallycompressed configuration and a radially expanded configuration, and aballoon positioned distally of said retention structure; said balloonbeing in communication with said passage of said conduit; and, a sheathdisposed over said conduit and said occlusion portion.
 11. The occlusionsystem of claim 10, wherein said balloon has a plurality of apertureslocated at its distal end.
 12. The occlusion system of claim 11, furthercomprising a tissue adhesive flowing from said proximal end of saidconduit, through said passage, into said balloon, and out of saidplurality of apertures.
 13. The occlusion system of claim 10, whereinsaid radially expandable retention structure is composed of braided meshthat is heat set to form an expanded, concave shape, an open cylindricalshape, or a flat disc shape.
 14. The occlusion system of claim 13,further comprising a detachment assembly connecting said conduit andsaid occlusion portion; said detachment assembly comprising a threadedmale portion engaged with a threaded female portion, such that rotationof said conduit detaches said conduit from said occlusion portion. 15.The occlusion system of claim 14, wherein said occlusion portion furthercomprises a valve between said at least one passage and an interior ofsaid balloon, such that when said occlusion portion is detached fromsaid conduit, said valve is closed.
 16. The occlusion system of claim10, wherein an exterior surface of said balloon is coated with tissueadhesive.
 17. The occlusion system of claim 10, wherein said ballooninflates to a generally conical shape.
 18. A method for treating a leftatrial appendage of a heart, comprising: advancing a conduit within apatient until an occlusion portion at a distal end of the conduit islocated at least partially within a left atrial appendage; expanding aretention structure so as to cover an opening of said left atrialappendage; inflating a balloon located within said left atrial appendageand distal of said retention structure; adhering said balloon to aninterior of said left atrial appendage with tissue adhesive; and,detaching said retention structure and said balloon from said conduit.19. The method of claim 18, wherein said inflating said balloon furthercomprises injecting said tissue adhesive into a passage of said conduitand into said balloon; and wherein said adhering said balloon furthercomprises allowing said tissue adhesive to escape through apertures insaid balloon.
 20. The method of claim 18, wherein said adhering saidballoon further comprises contacting an outer surface of said ballooncoated with tissue adhesive against said interior of said left atrialappendage.